Los Angeles County Sheriff's officials said there were no survivors from the morning crash on a rugged hillside in Calabasas, west of Los Angeles.

The helicopter was described as a Sikorsky S-76, Federal Aviation Administration spokesman Allen Kenitzer said.

Kobe Bryant's 13-year-old daughter Gianna was among the five fatalities in the helicopter crash which claimed the life of the NBA icon, Los Angeles Mayor Eric Garcetti said.

"L.A. is grieving with the Bryant family over the loss of Gianna, who perished with her father and friends in today's tragedy," Garcetti wrote on Twitter.

Gianna was one of Bryant's four children with wife Vanessa.

Bryant and Gianna had been flying to a game his daughter was expected to play in when their helicopter crashed, according to US reports.

TMZ was the first US media outlet to report that Bryant was among the fatalities, with the mayor of Calabasas later confirming the death of the 41-year-old Los Angeles Lakers icon to AFP.

Bryant's death sent shockwaves throughout the world, with fellow stars and celebrities expressing disbelief at the news.

"I'm stunned," wrote Hall-of-Fame NBA star Scottie Pippen. "Words can't even come close to describing it. Just an incredibly sad and tragic day."

"This can't be true," Dallas Mavericks star Luka Doncic wrote on Twitter. "No please." 

Tennis great Martina Navratilova added: "Gone much too soon, how devastating to hear of his passing, he gave joy to so many for so long - deep condolences to his family, his friends, his Lakers family. RIP Kobe." 

At the Staples Center in downtown Los Angeles, dozens of shocked fans gathered to pay tribute to the star.

Across the NBA, tributes broke out at two of eight games scheduled for Sunday.

Denver Nuggets fans began chants of "Kobe, Kobe" as a minute's silence was held before their game against the Houston Rockets.

Los Angeles Clippers coach Doc Rivers fought back tears ahead of his team's game against the Orlando Magic.

"Right now everybody is a Lakers fan. We're all Lakers right now,"Rivers said.

The crash came only hours after Bryant was passed by current Lakers star LeBron James for third on the all-time NBA scoring list in a Saturday game at Philadelphia.

Bryant's final post on social media had been a tweet congratulating James on surpassing him.

"Continuing to move the game forward @KingJames," Bryant wrote. "Much respect my brother #33644".

Bryant was a five-time NBA champion in a career that began in 1996 straight out of a high school and lasted until his retirement in 2016. 

He also was a two-time Olympic gold medalist, helping spark the US squad of NBA stars to titles in 2008 at Beijing and 2012 at London.